<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgl - USDZ exporter</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
		<style>
			body {
				background-color: #eee;
			}
			#info {
				color: #222;
			}
			a {
				color: #00f
			}
			#button {
				position: absolute;
				bottom: 15px;
				left: calc(50% - 40px);

			}
		</style>
	</head>

	<body>
		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - USDZ exporter<br />
			Battle Damaged Sci-fi Helmet by
			<a href="https://sketchfab.com/theblueturtle_" target="_blank" rel="noopener">theblueturtle_</a>
		</div>

		<a id="link" rel="ar" href="" download="asset.usdz">
			<img id="button" width="100" src="files/arkit.png">
		</a>

		<script type="module">

			import * as THREE from '../build/three.module.js';

			import { OrbitControls } from './jsm/controls/OrbitControls.js';
			import { RoomEnvironment } from './jsm/environments/RoomEnvironment.js';

			import { GLTFLoader } from './jsm/loaders/GLTFLoader.js';
			import { USDZExporter } from './jsm/exporters/USDZExporter.js';

			let camera, scene, renderer;

			init();
			render();

			function init() {

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.toneMapping = THREE.ACESFilmicToneMapping;
				renderer.outputEncoding = THREE.sRGBEncoding;
				document.body.appendChild( renderer.domElement );

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 0.25, 20 );
				camera.position.set( - 2.5, 0.6, 3.0 );

				const pmremGenerator = new THREE.PMREMGenerator( renderer );

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0xf0f0f0 );
				scene.environment = pmremGenerator.fromScene( new RoomEnvironment(), 0.04 ).texture;

				const loader = new GLTFLoader().setPath( 'models/gltf/DamagedHelmet/glTF/' );
				loader.load( 'DamagedHelmet.gltf', async function ( gltf ) {

					scene.add( gltf.scene );

					const shadowMesh = createSpotShadowMesh();
					shadowMesh.position.y = - 1.1;
					shadowMesh.position.z = - 0.25;
					shadowMesh.scale.setScalar( 2 );
					scene.add( shadowMesh );

					render();

					// USDZ

					const exporter = new USDZExporter();
					const arraybuffer = await exporter.parse( gltf.scene );
					const blob = new Blob( [ arraybuffer ], { type: 'application/octet-stream' } );

					const link = document.getElementById( 'link' );
					link.href = URL.createObjectURL( blob );

				} );

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.addEventListener( 'change', render ); // use if there is no animation loop
				controls.minDistance = 2;
				controls.maxDistance = 10;
				controls.target.set( 0, - 0.15, - 0.2 );
				controls.update();

				window.addEventListener( 'resize', onWindowResize );

			}

			function createSpotShadowMesh() {

				const canvas = document.createElement( 'canvas' );
				canvas.width = 128;
				canvas.height = 128;

				const context = canvas.getContext( '2d' );
				const gradient = context.createRadialGradient( canvas.width / 2, canvas.height / 2, 0, canvas.width / 2, canvas.height / 2, canvas.width / 2 );
				gradient.addColorStop( 0.1, 'rgba(130,130,130,1)' );
				gradient.addColorStop( 1, 'rgba(255,255,255,1)' );

				context.fillStyle = gradient;
				context.fillRect( 0, 0, canvas.width, canvas.height );

				const shadowTexture = new THREE.CanvasTexture( canvas );

				const geometry = new THREE.PlaneGeometry();
				const material = new THREE.MeshBasicMaterial( {
					map: shadowTexture, blending: THREE.MultiplyBlending, toneMapped: false
				} );

				const mesh = new THREE.Mesh( geometry, material );
				mesh.rotation.x = - Math.PI / 2;

				return mesh;

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

				render();

			}

			//

			function render() {

				renderer.render( scene, camera );

			}

		</script>

	</body>
</html>
